* Frosting in a metaphor for a layer cake represents something that adds a finishing touch, a final layer of embellishment or complexity.
* Occasionally suggests something that happens rarely, not adding a consistent layer.
* Honestly implies truthfulness, which is a quality, not a layer.
* Prescient means having foresight, which is an ability, not a layer.
* Frequently implies something that happens often, adding a consistent layer of action or occurrence on top of a base.
Therefore, "frequently" acts like frosting because it adds a layer of repetition or consistency to an underlying base, just as frosting adds a layer on top of cake.